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<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>

<body>
    <script>
        function Person(name) { this.name = name; }
        function one() {
            var a1 = new Person('a1');
            var a2 = new Person('a2');
            function two() {
                var b1 = new Person('b1');
                var b2 = new Person('b2');
                function three() {
                    console.log(a1, b1);
                }
                return three;
            }
            return two;


        }
        debugger
        let three = one()();
        debugger
        three();
    </script>
</body>

</html>